The teaser images show only close-ups of an STI badge on the grille and the fender vent of the car, representing Subaru Technica International, the company’s in-house tuning arm. Details are slim at this point, but Subaru showed a BRZ STI concept car at the 2011 Los Angeles auto show that featured larger wheels, a rear spoiler, and an aggressive body kit. We also spotted a high-performance Subaru BRZ testing on the Nurburgring last year that displayed STI wheels and brakes.We should see these kinds of upgrades for the STI version, but we’re not sure if these images are hinting at a full-bore, turbocharged factory STI model or a factory STI tuning kit for the BRZ. While there has long been speculation about a turbocharged version of the Subaru BRZ, it’s possible that these images are teasing something less dramatic. Also released over the weekend at the 86 Festival in Japan was a Subaru BRZ tS, meaning “tuned by STI,” which could be the model referenced in the teaser. This lightly tuned model will only be available in Japan and is powered by the same 2.0-liter flat-four that produces 200 hp and 151 lb-ft of torque in the standard car. Upgrades amount to new wheels and brakes, a body kit, Recaro seats, and a few other exterior and interior modifications.

Many enthusiasts have begged for more power since the Subaru BRZ’s debut, claiming that the car’s balanced chassis could easily handle extra horsepower. Although the aftermarket already provides numerous options for turbocharging and supercharging, it is still possible that a turbocharged STI version could be down the line. Look for more information to come about what STI is really hinting at here. We’re hoping it’s the turbocharged Subaru BRZ STI.Source: STI Japan,7tune.com

If they aren't going to put a turbo in it they might as well not even bother building it. An N/A BRZ with harder suspension that ruins the ride for marginally better (already great) handling and maybe another 20hp is just not worth it at all.